public class ZY3 {
    public static void main(String[] args) {
        Student a =new Student();
        Undergraduate b =new Undergraduate();
        a.name="张三";
        a.age=18;
        a.show();
        b.name="张三";
        b.age=18;
        b.degree="学士";
        b.show();

        Shape.AAA c=new Shape.AAA();
        System.out.println("圆的面积为："+c.Circle(3));
        System.out.println("正方形的面积为："+c.Square(2));
    }
}
